Harvester open publications of NAS Ukraine
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The concept and evaluating of big data quality in the semantic environment
Get PDFBig data refers to large volumes, complex data sets with various autonomous sources, characterized by continuous growth. Data storage and data collection capabilities are now rapidly expanding in all fields of science and technology due to the rapid development of networks. Evaluating the quality of data is a difficult task in the context of big data, because the speed of semantic data reasoning directly depends on its quality. The appropriate strategies are necessary to evaluate and assess data quality according to the huge amount of data and its rapid generation. Managing a large volume of heterogeneous and distributed data requires defining and continuously updating metadata describing various aspects of data semantics and its quality, such as conformance to metadata schema, provenance, reliability, accuracy and other properties. The article examines the problem of evaluating the quality of big data in the semantic environment. The definition of big data and its semantics is given below and there is a short excursion on a theory of quality assessment. The model and its components which allow to form and specify metrics for quality have already been developed. This model includes such components as: quality characteristics; quality metric; quality system; quality policy. A quality model for big data that defines the main components and requirements for data evaluation has already been proposed. In particular, such evaluation components as: accessibility, relevance, popularity, compliance with the standard, consistency, etc. are highlighted. The problem of inference complexity is demonstrated in the article. Approaches to improving fast semantic inference through materialization and division of the knowledge base into two components, which are expressed by different dialects of descriptive logic, are also considered below. The materialization of big data makes it possible to significantly speed up the processing of requests for information extraction. It is demonstrated how the quality of metadata affects materialization. The proposed model of the knowledge base allows increasing the qualitative indicators of the reasoning speed.Prombles in programming 2022; 3-4: 260-27
Process automatisation of Xcode new target creation
No full textWe live in the era of the Internet and technology. Now it is important for a person to be able to do their routine, uninteresting things quickly, and to be able to focus on more professional things. Everyone wants to minimize the time spent searching for information and have all services in one place.Due to these desires, significant progress is being made in the development of mobile applications. A number of factors also contribute to this. First, the development of the hardware of pocket-sized devices reaches a level sufficient for complex computing tasks. Secondly, the speed of Internet communication has increased. Third, almost everyone in the world now has a smartphone, so it is much more profitable for businesses to develop mobile applications to reach a wider audience. The development of applications for mobile devices is becoming more and more popular, but at the same time more expensive. In some cases, a business needs to have a number of similar applications for one reason or another. There are several approaches to code reuse in the context of iOS development. One is to use a common codebase and separate Xcode targets for each product. The process of creating a new target requires a number of routine operations, which require the programmer’s time, and writing code is potentially error-prone. This research proposes to improve this approach by using scripts to generate a project file based on given configurations. A console script for generating a project file and a project to illustrate the approach have been developed.Prombles in programming 2023; 1: 11-18
Simulations of human hemodynamic responses to blood temperature and volume changes
Get PDFAn advanced version (AV) of special software based on modified quantitative models of mechanisms that provide the overall control of human circulation is proposed. AV essentially expands the range of tasks concerning the modeling of cardiovascular physiology, in particular, the range of mechanisms controlling cardiac function, vascular hemodynamics, and total blood volume under unstable internal/ external physiochemical environments. The models are verified on data representing hemodynamic responses to certain physical tests. In the publication, two test scenarios, namely blood temperature and volume dynamic alterations, have been simulated and analyzed in detail. The user-friendly interface provides all stages of preparation and analysis of computer simulation. The PC-based simulator can also be used for educational purposes.Prombles in programming 2023; 1: 19-29
Image compression module based neural network autoencoders
No full textA new approach is proposed to data compression in the form of a neural network module based on the structure of autoencoders, which has the most optimal learning time, compression level and obtains sufficiently clear image reconstruction. The main mechanisms for building the structure of encoder and decoder neural networks, which are used as a module, have been developed. The main data for the reconstruction were selected from the open data set Fashion-MNIST, which allows simplified testing of neural network structures, the process of their training and obtaining results. Approaches to image reproduction using neural network layers of convolution and inverse convolution are analyzed. An analysis of the impact on the quality of the resulting image reconstruction of the structure of the output module, which is used to compress the input image, was carried out. Atypical behavior was found during the increase of layers in the structure of the autoencoder, which did not lead to an increase in the quality of image reproduction. The basic necessity of changing the structural parts of the autoencoder and its application in combination with other technologies to obtain a better reproduction result and the elimination of distortions is highlighted.Prombles in programming 2023; 1: 48-5
Вплив нічного освітлення на анатомічні і фізіологічні властивості листків липи, гіркокаштана і платана у садово-паркових і вуличних насадженнях Києва
No full textThe effect of nighttime lighting on the anatomical and morphological structure and the content of photosynthetic pigments in the leaves of Tilia cordata, Aesculus hippocastanum, and Platanus acerifolia was estimated on the example of garden-park and street plantings of Kyiv. At the experimental sites, the level of illumination and the soil surface temperature during the day and night periods were examined. The anatomical and morphological structure of the leaves was studied using transmission electron microscopy. The content of photosynthetic pigments (chlorophylls and carotenoids) in tree leaves was determined spectrophotometrically.The analysis of variance revealed that nighttime lighting significantly affected the anatomical structure and the content of photosynthetic pigments in the leaves of T. cordata and P. acerifolia. In A. hippocastanum, only parameters of stomata and palisade parenchyma showed a significant reaction to this stress factor
Ще один наслідок впливу нічного штучного світла
No full textUsing artificial light at night gives a lot of benefits for humanity, but, at the same time, it has changed our planet significantly. However, the problem was not taken seriously until its scale became noticeable. Though, skepticism, even among many recognized researchers, is still present, although this is expressed mainly in personal conversations. But, in any way the number of studies on this topic is increasing quite rapidly. Unfortunately, a part of these publications is not qualitative, published apparently without proper review, and this can seriously distort the understanding of the problem, have an impact on other scientific research, and also complicate the search for optimal ways to solve the problem of light pollution. One of such recently published works with the title “The effect of nighttime lighting on the anatomical and physiological features of the leaves of linden, horse chestnut, and plane trees in garden-park and street plantings of Kyiv” has caused a desire to pay attention to this situation, and to prevent similar ones in the future. So, the critical review of the mentioned study is presented here
Фізіологічні процеси Phalaenopsis pulcherrima за умов вирощування у гермооб’ємі
No full textThe hermetic condition is the least studied factor associated with the spaceflights. Phalaenopsis pulcherrima is promising for space farming as it can be cultivated in small substrate blocks, and its photosynthetic apparatus is well adapted to elevated CO2 concentrations and temperatures.Three-year-old meristematic P. pulcherrima plants were planted into plastic (acrylic) vessels filled with fibrous substrate. In control, vessels had an open top. The hermetic conditions were reached by sealing the vessels’ covers with a parafilm. Both control and hermetic vessels were placed in a plant growth chamber where test plants were cultivated under controlled conditions of air temperature, illumination, air humidity, and soil moisture. After 6 and 24 months of cultivation, the CO2 concentration in the hermetic and control vessels was measured, and the physiological characteristics of each test plant, such as the content of macro- and micronutrients, photosynthetic pigments, free amino acids, and content of labile carbohydrates (%) in the leaves of the test-plants were determined.It was revealed that cultivation of P. pulcherrima in hermetic conditions affected its basic physiological processes such as photosynthesis, mineral nutrition, carbohydrates, and amino acid metabolisms. The effect size of this stress factor depended on the duration of exposition period. Long-term cultivation of P. pulcherrima under hermetic conditions promoted the accumulation of nonenzymatic antioxidants (viz. chlorophyll b, carotenoids, and amino acids), which contributed to the adaptation of this orchid species to oxidative stress caused by hermetic environment
Мікроморфологія та анатомія плоду Iris pseudacorus L.
No full textBased on the suggestion that flower and fruit are integrally evolving structures, we aimed to reveal the floral traits persisting in the fruit structure in Iris pseudacorus, a widely distributed riparian species in Ukraine. We intended to compare the results with the other Iris species studied previously and reveal the constancy of micromorphological features of fruit interior structure. We revealed exomorphological and micromorphological peculiarities of the fruiting ovary using the model of vertical zonality of the gynoecium, vascular anatomy, and general anatomy of the fruit wall. In the fruiting ovary of I. pseudacorus, we revealed the presence of three vertical zones: short synascidiate zone, long symplicate zone bearing uniseriate seeds, and hemisymplicate zone located in the fruit beak. The vascular system of the ovary is composed of dorsal, septal, and ventral veins. Each of three dorsal veins divides radially into the outer tepal trace, stamen trace, and dorsal carpellary bundle, while each septal vein divides tangentially into three bundles of the inner tepal trace. Paired ventral veins enter the ovary from its bottom and supply ovules and seeds. The exocarp is composed of polygonal cells with thickened cellulose walls. The endocarp is uniseriate, unlignified, and composed of live prosenchymal cells, which are elongated tangentially. In the parenchymatous mesocarp, a great number of secretory canals with tannin-like content occur. The dehiscence of fruit on three valves proceeded by both dorsal and ventral slits. Dorsal slits are formed along dorsal grooves and provided by small-celled tissue surrounding the dorsal veins. The presence of ventral sutures of carpels in the symplicate zone of the ovary provides ventral dehiscence of fruit. Hence, the structure of the fruiting ovary in I. pseudacorus is comparable to that of other Iris species. Our investigation confirmed that the vertical zonality, placentation, and vascular system of the gynoecium in Iris can be appropriately estimated in the fruiting stage because the structural components of the ovary, which developed at the pre-anthetic phase, persist in the fruit
Decompositional Extraction and Retrieval of Conceptual Knowledge
Get PDFAn ability to extract hidden and implicit knowledge, their integration into a knowledge base, and then retrieval of required knowledge items are important features of knowledge processing for many modern knowledge-based systems. However, the complexity of these tasks depends on the size of knowledge sources, which were used for extraction, the size of a knowledge base, which is used for the integration of extracted knowledge, as well as the size of a search space, which is used for the retrieval of required knowledge items. Therefore, in this paper, we analyzed the internal semantic dependencies of homogeneous classes of objects and how they affect the decomposition of such classes. Since all subclasses of a homogeneous class of objects form a complete lattice, we applied the methods of formal concept analysis for the knowledge extraction and retrieval within the corresponding concept lattice. We found that such an approach does not consider internal semantic dependencies within a homogeneous class of objects, consequently, it can cause inference and retrieval of formal concepts, which are semantically inconsistent within a modeled domain. We adapted the algorithm for the decomposition of homogeneous classes of objects, within such knowledge representation model as object-oriented dynamic networks, to perform dynamic knowledge extraction and retrieval, adding additional filtration parameters. As the result, the algorithm extracts knowledge via constructing only semantically consistent subclasses of homogeneous classes of objects and then filters them according to the attribute and dependency queries, retrieving knowledge. In addition, we introduced the decomposition consistency coefficient, which allows estimation of how much the algorithm can reduce the search space for knowledge extraction and improves the performance. To demonstrate some possible application scenarios for the improved algorithm, we provided an appropriate example of knowledge extraction and retrieval via decomposition of a particular homogeneous class of objects.Prombles in programming 2022; 3-4: 139-15
On the peculiarities of using sparse matrices in problems of mathematical modeling
No full textMathematical modeling and the related computer experiment are now one of the main means of studying objects, processes and phenomena of various nature: in science, engineering, economics, society, etc. A significant improvement in the quality of mathematical modeling in many areas of science and engineering is possible only with the use of fundamentally new three-dimensional models, the transition from computer simulation of individual components and assemblies to the calculation and optimization of the product as a whole. It is obvious that the consideration of problems in such a formulation leads to discrete mathematical models of super-large sizes. Existing supercomputers of different parallel architectures make it possible to efficiently solve such problems. However, the time for solving problems on parallel computers consists of the time of the actual solution and the time of performing additional operations, that are necessary for the exchange of information between computing devices, that is overhead costs. This is especially true for problems of linear algebra with different structures of sparse matrices of large volumes, that arise in the mathematical modeling of processes. Sparse matrix compaction schemes, decomposition of data arrays between processors are one of the main factors for the effective solution of these problems on parallel computers. The paper considers efficient methods for processing sparse matrices of arbitrary structure for the purpose of effective mathematical modeling of structural strength problems on parallel computers. Various methods of regularization and decomposition of sparse matrices of arbitrary structure, efficient data storage schemes, technology for studying the conditionality of a matrix with approximate data on a computer are proposed. This way of using sparse matrices in mathematical modeling ensures more efficient use of computing resources and reliability of computer results. Problems of mathematical modeling are presented, where the considered methods of processing sparse matrices were effectively applied.Prombles in programming 2022; 3-4: 240-24